Feasibility and intra-and interobserver reproducibility of quantitative susceptibility mapping with radiomic features for intracranial dissecting intramural hematomas and atherosclerotic calcifications

Abstract

Quantitative susceptibility mapping (QSM) for 61 patients with dissecting intramural hematomas (n = 36) or atherosclerotic calcifications (n = 25) in intracranial vertebral arteries were collected to assess intra- and interobserver reproducibility in a 3.0-T MR system between January 2015 and December 2017. Two independent observers each segmented regions of interest for lesions twice. The reproducibility was evaluated using intra-class correlation coefficients (ICC) and within-subject coefficients of variation (wCV) for means and concordance correlation coefficients (CCC) and ICC for radiomic features (CCC and ICC > 0.85) were used. Mean QSM values were 0.277 ± 0.092 ppm for dissecting intramural hematomas and − 0.208 ± 0.078 ppm for atherosclerotic calcifications. ICCs and wCVs were 0.885–0.969 and 6.5–13.7% in atherosclerotic calcifications and 0.712–0.865 and 12.4–18.7% in dissecting intramural hematomas, respectively. A total of 9 and 19 reproducible radiomic features were observed in dissecting intramural hematomas and atherosclerotic calcifications, respectively. QSM measurements in dissecting intramural hematomas and atherosclerotic calcifications were feasible and reproducible between intra- and interobserver comparisons, and some reproducible radiomic features were demonstrated.

Assessing robustness of quantitative susceptibility-based MRI radiomic features in patients with multiple sclerosis

“…First-order features are confounded by large volumes due to the higher number of voxels within the VOI 59 ; thus, as NAWM was the largest VOI in our analysis, we expected a higher degree of variability and this was experimentally confirmed. A recent study assessing the reproducibility of QSM-derived radiomic features in dissecting intramural hematomas and atherosclerotic calcifications of intracranial vertebral arteries also observed volume-dependence of some features with the small volume of the VOIs jeopardising robustness 54 .…”

“…The Intraclass Correlation Coefficient (ICC) 53 was measured to evaluate robustness, with 1 indicating perfect repeatability and 0 complete lack of resemblance. Following previous practice 54 , features above a threshold level of ICC > 0.85 were considered to have good reliability. Initial evaluation was performed both overall and by hemisphere (left vs right); the two-sample t-test was used to assess differences between the two sides, with significant p-values < 0.05 considered significant.…”